[Is intrinsic or non-atopic asthma a particular disease?]

Intrinsic or non-atopic asthma is defined by the absence of positive skin test for specific aero-allergens, together with the absence of specific serum IgE. In the adult population, about one third of asthmatic patients are non-atopic. Non-atopic asthma begins generally later in life and is often more severe than atopic asthma. It is more often associated with chronic sinusitis and nasal polyps, a fact that is often underestimated. At the cellular and molecular level, non-atopic asthma and atopic asthma a very similar, and the reason for their clinical difference is not really understood.